The CALGB is comprised of 28 academic medical centers and over 200 affiliated community hospitals joined in the pursuit of improved cancer treatment and better understanding of tumor biology via the conduct of controlled clinical trials. Over 4000 members of the Group including oncology physicians, statisticians, clinical research associates, oncology nurses, pharmacists, epidemiologists, and basic scientists participate in these studies. From 25-35 phase III protocols are active at any one time, along with Phase II and Phase I studies that provide preliminary data required for the appropriate design of large scale randomized trials. In 2001 the CALGB accrued nearly 6662 entries to its protocols. Multidisciplinary disease committees of the Group design and implement protocols for the treatment of patients with leukemia, lymphoma, breast, respiratory, GI and GU cancer and melanoma. Modality committees, including Leukemia Correlative Sciences, Solid Tumor Correlative Sciences, Pharmacology and Experimental Therapeutics, Surgery, Pathology, Radiation Oncology, Transplant, Cancer in the Elderly, Cancer Control and Health Outcomes, Oncology Nursing, and Clinical Research Associates serve as the sites for planning and implementing new approaches for these disciplines. Major areas of emphasis in CALGB include development of innovative treatments for patients with cancer;studies of molecular predictors of prognosis and response to therapy;studies of the pharmacokinetics, pharmacodynamics and pharmacogenetics of new and established anticancer drugs;evaluation of minimally invasive surgical techniques;determining the cost and cost-effectiveness of new cancer therapies;evaluating the impact of cancer and its treatment on the quality of life of cancer patients and their caregivers;developing new strategies for cancer prevention;and addressing the needs of special populations, particularly minorities and the elderly. A new activity in Cancer Imaging will be initiated during the coming grant period in an effort to better integrate novel imaging science into cancer treatment studies.